Light emitting device

ABSTRACT

A light emitting device includes a plurality of light emitting elements and a light controller. The light emitting elements are for emitting lights. The light controller is disposed on the light emitting elements for the lights passing through, which is switchable in a first state and a second state. The light controller collimates the lights in the first state and diffuses the lights in the second state.

BACKGROUND OF THE DISCLOSURE 1. Field of the Disclosure

The present disclosure relates to a light emitting device, and moreparticularly to a light emitting device which can control or changedirection of light.

2. Description of the Prior Art

As the evolution and development of electronic devices, the electronicdevices have become an indispensable item. The electronic devices suchas display devices or light emitting devices can provide more convenientinformation transmission or image display. However, as the users attachimportance to privacy when viewing these devices, or as the safetyrequirements to prevent specific persons from viewing these devices areincreased (e.g., prevent the driver from watching the display device orthe light emitting device of the car while driving, or prevent thelights emitted by the display device or the light emitting device of thecar from being projected on the windshield to interfere with thedriver), these devices need to have the function of controlling thedirection of light.

SUMMARY OF THE DISCLOSURE

According to an embodiment, the present disclosure provides a lightemitting device including a plurality of light emitting elements and alight controller. The light emitting elements are emitting lights. Thelight controller is disposed on the light emitting elements for thelights passing through, which is switchable in a first state and asecond state. The light controller collimates the lights in the firststate and diffuses the lights in the second state.

According to another embodiment, the present disclosure provides a lightemitting device including a plurality of light emitting elements and alight controller. The light emitting elements are emitting lights. Thelight controller is disposed on the light emitting elements. The lightcontroller includes a plurality of cells for the light from the lightemitting elements passing through and a plurality of walls surroundingthe cells. The walls are switchable in states of a transmissive stateand a non-transmissive state.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram showing a top view of a light emittingdevice according to a first embodiment of the present disclosure.

FIG. 2 is a schematic diagram showing a cross-sectional view of thelight emitting device taken along a cross-sectional line A-A′ in FIG. 1.

FIG. 3 is a schematic diagram showing a cross-sectional view of astructure and lights of the light emitting device in a first state and astructure and lights of the light emitting device in a second stateaccording to the first embodiment of the present disclosure.

FIG. 4 is a schematic diagram showing a light controller in a firststate and a light controller in a second state according to the firstembodiment of the present disclosure.

FIG. 5 is a schematic diagram showing a top view of a light emittingdevice according to a second embodiment of the present disclosure.

FIG. 6 is a schematic diagram showing a cross-sectional view of thelight emitting device taken along a cross-sectional line B-B′ in FIG. 5.

FIG. 7 is a schematic diagram showing a cross-sectional view of thelight emitting device taken along a cross-sectional line C-C′ in FIG. 5.

FIG. 8 is a schematic diagram showing a cross-sectional view of a lightemitting device according to a third embodiment of the presentdisclosure.

FIG. 9 is a schematic diagram showing a cross-sectional view of astructure and lights of a light emitting device in a first state and astructure and lights of a light emitting device in a second stateaccording to a fourth embodiment of the present disclosure.

FIG. 10 is a schematic diagram showing a cross-sectional view of astructure and lights of a light emitting device in a first state and astructure and lights of a light emitting device in a second stateaccording to a fifth embodiment of the present disclosure.

FIG. 11 is a schematic diagram showing a cross-sectional view of astructure and lights of a light emitting device in a first state and astructure and lights of a light emitting device in a second stateaccording to a sixth embodiment of the present disclosure.

DETAILED DESCRIPTION

The present disclosure may be understood by reference to the followingdetailed description, taken in conjunction with the drawings asdescribed below. It is noted that, for purposes of illustrative clarityand being easily understood by the readers, various drawings of thisdisclosure show a portion of a light emitting device in this disclosure,and certain elements in various drawings may not be drawn to scale. Inaddition, the number and dimension of each device shown in drawings areonly illustrative and are not intended to limit the scope of the presentdisclosure.

Certain terms are used throughout the description and following claimsto refer to particular components. As one skilled in the art willunderstand, electronic equipment manufacturers may refer to a componentby different names. This document does not intend to distinguish betweencomponents that differ in name but not function. In the followingdescription and in the claims, the terms “include”, “comprise” and“have” are used in an open-ended fashion, and thus should be interpretedto mean “include, but not limited to . . . ”. Thus, when the terms“include”, “comprise” and/or “have” are used in the description of thepresent disclosure, the corresponding features, areas, steps, operationsand/or components would be pointed to existence, but not limited to theexistence of one or a plurality of the corresponding features, areas,steps, operations and/or components.

The directional terms used throughout the description and followingclaims, such as: “on”, “up”, “above”, “down”, “below”, “front”, “rear”,“back”, “left”, “right”, etc., are only directions referring to thedrawings. Therefore, the directional terms are used for explaining andnot used for limiting the present disclosure. Regarding the drawings,the drawings show the general characteristics of methods, structures,and/or materials used in specific embodiments. However, the drawingsshould not be construed as defining or limiting the scope or propertiesencompassed by these embodiments. For example, for clarity, the relativesize, thickness, and position of each layer, each area, and/or eachstructure may be reduced or enlarged.

When the corresponding component such as layer or area is referred to“on another component”, it may be directly on this another component, orother component(s) may exist between them. On the other hand, when thecomponent is referred to “directly on another component (or the variantthereof)”, any component does not exist between them. Furthermore, whenthe corresponding component is referred to “on another component”, thecorresponding component and the another component have a dispositionrelationship along a top-view/vertical direction, the correspondingcomponent may be below or above the another component, and thedisposition relationship along the top-view/vertical direction aredetermined by an orientation of the device.

It will be understood that when a component or layer is referred to asbeing “connected to” another component or layer, it can be directlyconnected to this another component or layer, or intervening componentsor layers may be presented. In contrast, when a component is referred toas being “directly connected to” another component or layer, there areno intervening components or layers presented. In addition, when thecomponent is referred to “be coupled to/with another component (or thevariant thereof)”, it may be directly connected to this anothercomponent, or may be indirectly connected (such as electricallyconnected) to this another component through other component(s).

The terms “about”, “substantially”, “equal”, or “same” generally meanwithin 20% of a given value or range, or mean within 10%, 5%, 3%, 2%,1%, or 0.5% of a given value or range.

Although terms such as first, second, third, etc., may be used todescribe diverse constituent elements, such constituent elements are notlimited by the terms. These terms are used only to discriminate aconstituent element from other constituent elements in thespecification, and these terms have no relation to the manufacturingorder of these constituent components. The claims may not use the sameterms, but instead may use the terms first, second, third, etc. withrespect to the order in which an element is claimed. Accordingly, in thefollowing description, a first constituent element may be a secondconstituent element in a claim.

It should be noted that the technical features in different embodimentsdescribed in the following can be replaced, recombined, or mixed withone another to constitute another embodiment without departing from thespirit of the present disclosure.

In the present disclosure, the light emitting device may optionallyinclude a display function, a sensing function, a touch sensingfunction, an antenna function, other suitable function or a combinationthereof, but not limited thereto. In some embodiments, the lightemitting device may include a tiled device, but not limited thereto. Thelight emitting device may include liquid crystal (LC) molecules, anorganic light-emitting diode (OLED), an inorganic light-emitting diode(LED) such as a micro-LED and/or a mini-LED, quantum dots (QDs)material, a quantum-dot light-emitting diode (QLED, QDLED), fluorescencematerial, phosphor material, other suitable material or a combinationthereof, but not limited thereto. Moreover, the light emitting devicemay include a color light emitting device or a monochrome light emittingdevice, and a shape of the light emitting device may be a rectangle, acircle, a polygon, a shape having a curved edge or other suitable shape,but not limited thereto. In the following, in order to explainexemplarily, the light emitting device is a color light emitting devicehaving light-emitting diodes (e.g., organic light-emitting diodes,inorganic light-emitting diodes or quantum-dot light-emitting diodes) asan example, but the light emitting device is not limited thereto. Insome embodiments, the light emitting device may include a liquid crystalpanel or be other suitable light emitting device.

Referring to FIG. 1 and FIG. 2, FIG. 1 is a schematic diagram showing atop view of a light emitting device according to a first embodiment ofthe present disclosure, FIG. 2 is a schematic diagram showing across-sectional view of the light emitting device taken along across-sectional line A-A′ in FIG. 1. As shown in FIG. 1 and FIG. 2, thelight emitting device 100 of this embodiment includes a first substrate110, a plurality of light emitting elements 120, a light controller 130,a first control electrode E1 and a second control electrode E2, and thelight emitting device 100 may optionally include a second substrate 140.Each structure and each component will be described as below. FIG. 1only shows nine light emitting elements 120 as an example, but the lightemitting device 100 may include fewer or more light emitting elements120 in fact. The first substrate 110 may be disposed opposite to thesecond substrate 140, and the light emitting elements 120, the lightcontroller 130, the first control electrode E1 and the second controlelectrode E2 may be disposed between the first substrate 110 and thesecond substrate 140. The first substrate 110 and the second substrate140 may individually include glass, quartz, sapphire, polyimide (PI),polyethylene terephthalate (PET), other suitable material or acombination thereof, so as to be a rigid substrate or a flexiblesubstrate, but not limited thereto. The material of the first substrate110 and the material of the second substrate 140 may be the same ordifferent. Note that the light emitting device 100 has an illuminatingsurface LS, the illuminating surface LS is an outermost surface whichthe light provided from the light emitting device 100 passes through.For example, in the embodiment shown in FIG. 2, the illuminating surfaceLS may be an outer surface of the second substrate 140, but not limitedthereto.

In FIG. 2, the light emitting elements 120 may be disposed on the firstsubstrate 110, and may be configured to emit lights. Note that, in thelights generated by the light emitting elements 120, the presentdisclosure only discusses the lights emitted towards the illuminatingsurface LS, wherein the emitted direction of the light emitted towardsthe illuminating surface LS has a positive component parallel to aupward normal direction Dn of the first substrate 110 (hereafter,referred as the normal direction Dn), and the lights emitted towards theilluminating surface LS may be lights directly emitted from the lightemitting elements 120 and/or reflected lights emitted from the lightemitting elements 120 and reflected by other component(s). In thepresent disclosure, the light emitting element 120 may generate thelight with the intensity corresponding to the signal (e.g., gray levelsignal). For instance, if the light emitting device 100 is configured todisplay an image, each light emitting element 120 may generate the lightwith the intensity corresponding to the gray level signal of the image.In some embodiments, the light emitting element 120 may be aself-luminous type component, such as an organic light-emitting diode,an inorganic light-emitting diode (e.g., micro-LED and/or a mini-LED) ora quantum-dot light-emitting diode, but not limited thereto. In someembodiments, the light emitting element 120 may be corresponding to asub-pixel in a liquid crystal panel. Thus, the light emitting element120 may adjust the liquid crystal molecules in the light emittingelement 120 according to the gray level signal of the image, such thatthe transmittance of the backlight may be adjusted, and the lightemitting element 120 may generate the light with the intensitycorresponding to the gray level signal of the image, but not limitedthereto. Note that, if the light emitting element 120 is the sub-pixelin the liquid crystal panel, the first substrate 110 of the lightemitting device 100 may be a substrate having a driving circuitconfigured to drive the liquid crystal molecules in the liquid crystalpanel.

In some embodiments, the light emitting elements 120 may generate thelights with a plurality of colors. For example, the light emittingelements 120 may include at least one first light emitting elementemitting red light, at least one second light emitting element emittinggreen light and at least one third light emitting element emitting bluelight, such that the light emitting device 100 may generate coloredlight to be a colored light emitting device, but not limited thereto.For another example, the light emitting elements 120 may emit red light,green light, blue light and yellow light, but not limited thereto. Insome embodiments, all of the light emitting elements 120 may emit thesame color light, and the light emitting device 100 may further includea light converting layer disposed on the light emitting element 120, soas to convert (or filter) the light emitted from the light emittingelement 120 into another light with different color, wherein the lightconverting layer may be disposed at any suitable position between theilluminating surface LS and the light emitting element 120. The lightconverting layer may include color filter, quantum dots (QD) material,fluorescence material, phosphorescence material, other suitable materialor a combination thereof. For instance, the light emitting elements 120may emit white light, and the light converting layer may include a firstlight converting part converting the white light into the red light, asecond light converting part converting the white light into the greenlight and a third light converting part converting the white light intothe blue light, such that the light emitting device 100 may generatecolored light to be a colored light emitting device, but not limitedthereto. For another example, the light emitting elements 120 may emitblue light, and the light converting layer may include a first lightconverting part converting the blue light into the red light and asecond light converting part converting the blue light into the greenlight, such that the light emitting device 100 may generate coloredlight to be a colored light emitting device, but not limited thereto. Insome embodiments, all of the light emitting elements 120 may emit thesame color light, such that the light emitting device 100 may be amonochrome light emitting device, but not limited thereto.

Moreover, the light emitting device 100 may further include at least oneswitching component (not shown in figures), and each switching componentmay be electrically connected to one or more light emitting element(s)120, or electrically connected to one or more component(s) in the lightemitting element(s) 120, wherein the light emitting element 120 maychange the intensity of its emitting light according to the switchingstate of the switching component which it is electrically connected. Insome embodiments, the switching component may be a thin film transistor(TFT) or other suitable switch, wherein the thin film transistor may besuch as a top gate thin film transistor, a bottom gate thin filmtransistor, a dual gate thin film transistor or other suitabletransistor.

The light emitting device 100 may further include a plurality ofconductive lines to be electrically connected to the electroniccomponent(s) in the light emitting device 100. In some embodiments, theconductive lines may include a plurality of first conductive lines 111and a plurality of second conductive lines 112 disposed on the firstsubstrate 110. Each first conductive line 111 may be electricallyconnected to or coupled to such as the light emitting element(s) 120,the component(s) in the light emitting element(s) 120 and/or theswitching component(s), and each second conductive line 112 may beelectrically connected to or coupled to such as the light emittingelement(s) 120, the component(s) in the light emitting element(s) 120and/or the switching component(s). In some embodiments, the firstconductive line 111 may be electrically connected between one end (e.g.,a source) of the switching component and a circuit (e.g., an integratedcircuit) providing the gray level signal, such that the first conductiveline 111 may serve as a signal line or a data line; the secondconductive line 112 may be electrically connected between another end(e.g., a gate) of the switching component and a circuit (e.g., anintegrated circuit and/or a gate driving circuit) providing a switchingsignal, such that the second conductive line 112 may serve as a scanline, but not limited thereto. The connection of the conductive line maybe adjusted based on the circuit design. Accordingly, in one of thelight emitting elements 120, if the switching component is turned onbased on the switching signal, the light emitting element 120 maygenerate the light having the intensity corresponding to the gray levelsignal. In some embodiments, the first conductive line 111 and thesecond conductive line 112 may be a line which has slight waves andsubstantially extends along a direction rather than a straight line.Furthermore, in some embodiments, the first conductive lines 111 may besubstantially parallel to each other, the second conductive lines 112may be substantially parallel to each other, and the first conductiveline 111 and the second conductive line 112 may not be parallel to eachother. For instance, the first conductive line 111 and the secondconductive line 112 may be substantially perpendicular to each other,but not limited thereto. The above only describes the first conductivelines 111 and the second conductive lines 112 as an example, but otherconductive line(s) can be added based on requirement(s).

In FIG. 2, the light emitting device 100 may optionally include aninsulating layer 150 disposed on the light emitting element(s) 120. Insome embodiments, the insulating layer 150 may have a protectingfunction to protect the light emitting element(s) 120 covered by theinsulating layer 150. In some embodiments, the insulating layer 150 maybe further disposed on the switching component(s) and the conductiveline(s), so as to protect the switching component(s) and the conductiveline(s).

The forming methods of the light emitting element 120, the switchingcomponent, the conductive line and the insulating layer 150 may beadjusted based on requirement(s) and/or the type of the light emittingelement 120. In some embodiments, the light emitting device 100 mayinclude a circuit component layer disposed on the first substrate 110,wherein the circuit component layer may include a plurality of layers,and these layers may form the light emitting element 120, the switchingcomponent, the conductive line (e.g., the first conductive line 111and/or the second conductive line 112) and the insulating layer 150. Indetail, the layers in the circuit component layer may include at leastone conductive layer, at least one interlayer insulating layer, at leastone semiconductor layer, other suitable layer or a combination thereof.The material of the conductive layer may include metal, transparentconductive material (such as indium tin oxide (ITO), indium zinc oxide(IZO), etc.), other suitable conductive material or a combinationthereof. The material of the interlayer insulating layer may includesuch as silicon oxide (SiO_(x)), silicon nitride (SiN_(y)), siliconoxynitride (SiO_(x)N_(y)), polymethylmetacrylate (PMMA), other suitableinsulating material or a combination thereof. The material of thesemiconductor layer may include such as poly-silicon, amorphous silicon,metal-oxide semiconductor (e.g., IGZO), other suitable semiconductormaterial or a combination thereof, but not limited thereto. These layersin the circuit component layer may be formed by at least onesemiconductor process(es) such as a deposition process, an etch processand/or a photolithography. Namely, the light emitting element 120 (forexample, but not limited to, the organic light-emitting diode), theswitching component, the conductive line and the insulating layer 150may be formed by the semiconductor process(es), but not limited thereto.In some embodiments, the layers in the circuit component layer may formthe switching component and the conductive line, and the light emittingelement 120 (for example, but not limited to, the inorganiclight-emitting diode) may be disposed on the circuit component layer bya bonding process; then, the insulating layer 150 is formed on the lightemitting element 120, but not limited thereto. In some embodiments, thelayers in the circuit component layer may form the switching component,the conductive line and at least one component of the light emittingelement 120, and other component(s) of the light emitting element 120may be formed on the circuit component layer by other suitablemethod(s). For instance, if the light emitting element 120 is thesub-pixel in the liquid crystal panel, a pixel electrode of the lightemitting element 120 may be included in the circuit component layer, andthe liquid crystal molecules are disposed on the circuit componentlayer. Note that, if the light emitting element 120 is the sub-pixel inthe liquid crystal panel, the insulating layer 150 may be anothersubstrate of the liquid crystal panel, and this another substrate isopposite to the substrate having the driving circuit configured to drivethe liquid crystal molecules.

The layers in the circuit component layer may be further configured toform other required electronic component(s) and/or structure(s). In someembodiments, the light emitting device 100 may further include otherrequired active component(s) and/or passive component(s) disposed in thecircuit component layer. For instance, based on requirement(s), thelight emitting device 100 may further include a capacitor, and thecapacitor may be electrically connected to the light emitting element120 or the component(s) of the light emitting element 120, but notlimited thereto.

As shown in FIG. 2, the light controller 130, the first controlelectrode E1 and the second control electrode E2 are disposed on thelight emitting elements 120, wherein the first control electrode E1 andthe second control electrode E2 may control the state of the lightcontroller 130 based on the received control signal. In the differentstates of the light controller 130, the lights generated by the lightemitting elements 120 may have different types of radiating directionsafter they pass through the light controller 130. In some embodiments(as shown in FIG. 2), the light controller 130 may include a pluralityof switchable diffusers 132 and a plurality of light shielding elements134, wherein the switchable diffuser 132 may be disposed correspondingto (or overlapped with) at least one of the light emitting elements 120in the normal direction Dn, and the light shielding element 134 may bedisposed between two adjacent switchable diffusers 132. Therefore, thelight shielding element 134 may be not corresponding to (or notoverlapped with) the light emitting element 120 in the normal directionDn. For example, in FIG. 1 and FIG. 2, the switchable diffuser 132 maybe corresponding to (or overlapped with) one light emitting element 120in the normal direction Dn, but not limited thereto. In this embodiment,the lights generated by the light emitting elements 120 may pass throughthe switchable diffusers 132, and the light shielding elements 134 mayshield the lights generated by the light emitting elements 120, whereinthe light shielding element 134 may have a side wall 134 a capable ofadjusting the light path (e.g., an angle θ between the side wall 134 aand the illuminating surface LS may be, but not limited to, greater thanor equal to 80°). Note that the side wall 134 a may substantially extendalong an extending direction and not be a flatten surface, and the angleθ may be between this extending direction and the illuminating surfaceLS. The light shielding elements 134 may include photoresist, black ink,black resin, gray ink, gray resin, white ink, white resin, pigment, dye,other suitable light shielding material or a combination thereof. Inaddition, the dispositions of the switchable diffusers 132 and the lightshielding elements 134 may be designed based on requirement(s). Forinstance, in some embodiments (as shown in FIG. 2), the light controller130 may be a single layer structure including the switchable diffusers132 and the light shielding elements 134, and thus, the switchablediffusers 132 and the light shielding elements 134 included in thesingle layer structure may be alternated arranged in a horizontaldirection (the horizontal direction is perpendicular to the normaldirection Dn), but not limited thereto. For instance, in someembodiments (as shown in FIG. 2), the light shielding elements 134 maysurround the switchable diffusers 132 in top view, but not limitedthereto. For instance, in some embodiments (as shown in FIG. 1 and FIG.2), two adjacent switchable diffusers 132 may be completely separated bythe light shielding element(s) 134, but not limited thereto. Moreover,in some embodiments (as shown in FIG. 1), in the normal direction Dn,the first conductive line 111 and the second conductive line 112 maycross over some light shielding elements 134 and some switchablediffusers 132, but not limited thereto. In some embodiments (not shownin figures), in the normal direction Dn, the first conductive line 111and the second conductive line 112 may overlap the light shieldingelement(s) 134 and not overlap the switchable diffuser(s) 132, but notlimited thereto.

Since the first control electrode E1 and the second control electrode E2need to control the state of the light controller 130, the first controlelectrode E1 and the second control electrode E2 may be disposedadjacent to the light controller 130. In this embodiment, the firstcontrol electrode E1 and the second control electrode E2 may control theswitchable diffusers 132 based on the received control signal, so as tocontrol the state of the light controller 130. Thus, the first controlelectrode E1 and the second control electrode E2 may be at leastadjacent to the switchable diffusers 132 of the light controller 130. Insome embodiments, the state of the light controller 130 may becontrolled by a voltage difference between the first control electrodeE1 and the second control electrode E2 (or controlled by an electricfield between the first control electrode E1 and the second controlelectrode E2), but not limited thereto. In some embodiments (as shown inFIG. 2), the first control electrode E1 and the second control electrodeE2 of the light emitting device 100 may be disposed on two oppositesides of the light controller 130 respectively, wherein the firstcontrol electrode E1 is between the light controller 130 and the firstsubstrate 110, the second control electrode E2 is between the lightcontroller 130 and the second substrate 140, but not limited thereto. Insome embodiments, the first control electrode E1 and the second controlelectrode E2 of the light emitting device 100 may be disposed on thesame side of the light controller 130, but not limited thereto. Inaddition, the material of the first control electrode E1 and thematerial of the second control electrode E2 may individually includemetal, transparent conductive material (such as indium tin oxide (ITO),indium zinc oxide (IZO), etc.), other suitable conductive material or acombination thereof. In this embodiment, since the lights generated bythe light emitting elements 120 may pass through the switchablediffusers 132, a portion of the first control electrode E1 and a portionof the second control electrode E2 corresponding to the switchablediffusers 132 have high transparency, and no restrictions on otherportion of the first control electrode E1 and other portion of thesecond control electrode E2. For example, in some embodiments, thematerial of the portion of the first control electrode E1 and thematerial of the portion of the second control electrode E2 correspondingto the switchable diffusers 132 may be transparent conductive material,and the material of other portion of the first control electrode E1 andthe material of other portion of the second control electrode E2 may bemetal to reduce the resistance of these control electrodes; in someembodiments, the first control electrode E1 and the second controlelectrode E2 may be respectively transparent conductive layers to reducethe manufacturing cost, but not limited thereto. In some embodiments,the first control electrode E1 and the second control electrode E2 maybe patterned, but not limited thereto. Moreover, the light emittingdevice 100 may further include a plurality of peripheral traces PT, thecircuit (e.g., an integrated circuit) providing the control signal maybe electrically connected to the first control electrode E1 and thesecond control electrode E2 by the peripheral traces PT respectively.The peripheral traces PT may include any suitable conductive material,such as metal, but not limited thereto.

Referring to FIG. 3 and FIG. 4, FIG. 3 is a schematic diagram showing across-sectional view of a structure and lights of the light emittingdevice in a first state and a structure and lights of the light emittingdevice in a second state according to the first embodiment of thepresent disclosure, FIG. 4 is a schematic diagram showing a lightcontroller in a first state and a light controller in a second stateaccording to the first embodiment of the present disclosure, wherein thefirst conductive line and the second conductive line are omitted in FIG.3 to make FIG. 3 clear. Note that FIG. 3 uses different shadings to showthe switchable diffusers 132 in different states, wherein the switchablediffusers 132 in a first state SU1 are shown by sparsely dotted shading,and the switchable diffusers 132 in a second state SU2 are shown bydensely dotted shading. Note that FIG. 4 only shows the first controlelectrode E1, the second control electrode E2 and the switchablediffusers 132 to make FIG. 4 clear. As shown in FIG. 3, regarding theoperation of the light controller 130, the light controller 130 may beswitched between the first state SU1 and the second state SU2 accordingto the control signals received by the first control electrode E1 andthe second control electrode E2, wherein the light controller 130 maycollimate the lights generated by the light emitting elements 120 in thefirst state SU1, and the light controller 130 may diffuse the lightsgenerated by the light emitting elements 120 in the second state SU2.Note that, in the present disclosure, the collimation and the diffusionof the lights may be confirmed by measuring output lights passingthrough the illuminating surface LS (the lights generated by the lightemitting elements 120 are referred as the output lights after passingthrough the illuminating surface LS). The collimated lights mean thatthe sum of the intensity of the output lights of which the angle withthe illuminating surface LS ranges from 80° to 100° is greater than orequal to 80% of the total intensity of the output lights. That is tosay, when the sum of the intensity of the output lights of which theangle with the normal direction of the illuminating surface LS rangesfrom −10° to +10° is greater than or equal to 80% of the sum of theintensity of the output lights with all angles (i.e., the angle with thenormal direction of the illuminating surface LS ranges from −90° to+90°), the output lights are collimated. The diffused lights mean thatthe intensity of the output lights within the observable viewing angleof the light emitting device 100 has only a small difference withoutrapid changes (i.e., the output lights are substantially uniformlyscattered within the observable viewing angle of the light emittingdevice 100, and there is no area has concentrated output lights). Thus,under the condition that the output lights are diffused, the sum of theintensity of the output lights of which the angle with the illuminatingsurface LS ranges from 80° to 100° may be less than 80% of the totalintensity of the output lights.

As shown in FIG. 3, the emitted directions of the lights generated bythe light emitting elements 120 may be various and direct to theilluminating surface LS. When these lights are emitted to the lightcontroller 130 which is in different states (such as the first state SU1and the second state SU2), the emitted directions of these lights in thelight controller 130 may be adjusted and/or filtered by the lightcontroller 130. In detail, first, before the lights enter the lightcontroller 130, a portion of the lights (i.e., the lights L1 of whichthe angle with the normal direction Dn is greater) may be blocked by abottom surface of the light shielding element(s) 134, and anotherportion of the lights may enter the switchable diffuser 132 to beadjusted and/or filtered. In the first state SU1 of this embodiment, theswitchable diffusers 132 may not adjust the emitted directions (in thelight controller 130) of the lights generated by the light emittingelements 120 (e.g., the switchable diffusers 132 are almosttransparent). Therefore, when the lights generated by the light emittingelements 120 enter the switchable diffusers 132 in the first state SU1,the lights (e.g., the lights L2) of which the angle with the normaldirection Dn is greater may be blocked by the side walls 134 a of thelight shielding elements 134, such that the lights may be collimated andpass through the illuminating surface LS (e.g., the lights L3). On theother hand, in the second state SU2 of this embodiment, the switchablediffusers 132 may adjust the emitted directions (in the light controller130) of the lights generated by the light emitting elements 120 (e.g.,the switchable diffusers 132 may make the lights be diffused), andtherefore, the lights may be uniformly diffused and pass through theilluminating surface LS (e.g., the lights L4). Accordingly, it can beknown that, in the first state SU1 of this embodiment, the lightcontroller 130 may collimate the lights by the light shielding elements134; in the second state SU2 of this embodiment, the light controller130 may diffuse the lights by the switchable diffusers 132.

In another aspect, in the light controller 130, the switchable diffuser132 may have a first haze in the first state SU1, and the switchablediffuser 132 may have a second haze in the second state SU2. Note that,the haze of the object described in the present disclosure representsthat the percentage of the intensity of the transmitted lights whichdeviate from their incident lights by more than 2.5° to the totalintensity of the transmitted light. In some embodiments, the first hazemay be less than 10, and/or the second haze may be greater than 90, butnot limited thereto. As shown in FIG. 4, in order to make the switchablediffuser 132 have different functions (i.e., the haze and/or the abilityto change the light path) in different states, the light emitting device100 may provide an alternating current (AC) control signal with a firstvoltage difference V1 for the first control electrode E1 and the secondcontrol electrode E2 in the first state SU1, and the light emittingdevice 100 may provide an alternating current control signal with asecond voltage difference V2 for the first control electrode E1 and thesecond control electrode E2 in the second state SU2, wherein the voltagedifference of the alternating current control signal represents themaximum voltage difference between the signals of the two electrodes atthe same time. In some embodiments, the absolute value of the firstvoltage difference V1 may be greater than the absolute value of thesecond voltage difference V2, and/or the second voltage difference V2may be close to 0, but not limited thereto. In some embodiments, theabsolute value of the first voltage difference V1 may be less than theabsolute value of the second voltage difference V2, and/or the firstvoltage difference V1 may be close to 0, but not limited thereto.

According to the above, the switchable diffuser 132 may include anysuitable material which can achieve the above function. In someembodiments, each switchable diffuser 132 may be a polymer dispersedliquid crystal cell (PDLC), a polymer network liquid crystal cell(PNLC), other suitable material or a combination thereof. The polymerdispersed liquid crystal cell and the polymer network liquid crystalcell may be respectively mixed with different polymer materials to formdifferent crosslink structures. The thickness of the liquid crystallayer in the polymer network liquid crystal cell is thinner and needsthe alignment layer(s); then, since the polymer network liquid crystalcell can be driven by the lower driving voltage, it can save the power.Since the liquid crystal layer in the polymer dispersed liquid crystalcell does not need the alignment layer, its manufacturing cost is lower.Furthermore, the molecules in the switchable diffuser 132 may havedifferent arrangements in the first state SU1 and the second state SU2.For instance, in FIG. 4, the molecules in the switchable diffuser 132may be substantially parallel to each other in the first state SU1 (themolecules have the similar tilt angle), and the molecules in theswitchable diffusers 132 may not have the similar tilt angle in thesecond state SU2, but not limited thereto. The switchable diffuser 132may use other type medium based on requirement(s).

In addition, the forming methods of the light controller 130, the firstcontrol electrode E1 and the second control electrode E2 are notparticularly limited. In some embodiments (as shown in FIG. 2), thefirst control electrode E1 and the second control electrode E2 may berespectively formed on the insulating layer 150 and the second substrate140 by a coating process, a deposition process and/or othersemiconductor process(es), and the light shielding elements 134 may beformed on the first control electrode E1 by a coating process, adeposition process and/or other semiconductor process(es). Then, thefirst substrate 110 and the second substrate 140 may be adhered to eachother by such as sealant AL, thereby assembling the first substrate 110and the second substrate 140. Finally, the switchable diffusers 132 maybe disposed between the first substrate 110 and the second substrate140, so as to complete the manufacture, but not limited thereto. Notethat, the sealant AL may be used to reduce the leakage of material inthe switchable diffuser 132 in addition to assembling the firstsubstrate 110 and the second substrate 140. In some embodiments, thefirst control electrode E1, the light shielding element 134, theswitchable diffuser 132 and the second control electrode E2 may bedisposed on the insulating layer 150 in sequence, but not limitedthereto.

According to the above, compared with the traditional electronic devicewith the function of controlling the light direction, the light emittingdevice 100 of the present disclosure may be thinner, and/or the lightemitting device 100 of the present disclosure may have the simplifiedstructure. Moreover, when each light emitting element 120 may be aself-luminous type component, and each light emitting element 120 maygenerate the light with the intensity corresponding to the gray levelsignal of the image, the light emitting device 100 may be thinner evenand/or may have the more simplified structure.

Moreover, the light emitting device 100 may further include othersuitable component(s) and/or structure(s) based requirement(s). In someembodiments, the light emitting device 100 may optionally include anoptical layer, such as a polarizer and/or an anti-reflection film,disposed at any suitable position, but not limited thereto. In someembodiments, the light emitting device 100 may optionally include anelectrically controlled birefringence (ECB) component disposed on thelight controller 130. The electrically controlled birefringencecomponent may be configured to decrease lateral light leakage.Therefore, the electrically controlled birefringence component may makethe lights generated by the light emitting device 100 in the first stateSU1 have higher light collimation. For instance, if the light emittingdevice 100 has the electrically controlled birefringence component, inthe lights generated by the light emitting device 100 in the first stateSU1, the sum of the intensity of the output lights of which the anglewith the illuminating surface LS ranges from 80° to 100° may be enhanced(e.g., this sum may be greater than or equal to 90% of the totalintensity of the output lights), but not limited thereto.

The light emitting device of the present disclosure is not limited tothe above embodiments. Further embodiments of the present disclosure aredescribed below. For ease of comparison, same components will be labeledwith the same symbol in the following. The following descriptions relatethe differences between each of the embodiments, and repeated parts willnot be redundantly described.

Referring to FIG. 5 to FIG. 7, FIG. 5 is a schematic diagram showing atop view of a light emitting device according to a second embodiment ofthe present disclosure, FIG. 6 is a schematic diagram showing across-sectional view of the light emitting device taken along across-sectional line B-B′ in FIG. 5, and FIG. 7 is a schematic diagramshowing a cross-sectional view of the light emitting device taken alonga cross-sectional line C-C′ in FIG. 5, wherein FIG. 5 only shows ninelight emitting elements 120 as an example, but the light emitting device200 may include fewer or more light emitting elements 120 in fact. Also,the first conductive line and the second conductive line are omitted inFIG. 5 to FIG. 7 to make figures clear. As shown in FIG. 5 to FIG. 7, adifference between this embodiment and the first embodiment is that thelight emitting device 200 of this embodiment may further include aplurality of first spacers SP1, and the first spacer SP1 is disposedbetween the light shielding element 134 and the second control electrodeE2. For instance, in FIG. 7, the first spacer SP1 is in contact with thelight shielding element 134 and the second control electrode E2simultaneously, but not limited thereto. The arrangement of the firstspacers SP1 in top view, the number of the first spacers SP1 and thedensity of the first spacers SP1 may be adjusted based onrequirement(s). For example, in FIG. 5, in top view, the first spacerSP1 may be disposed at a geometric center of a smallest regioncontaining some light emitting elements 120 (FIG. 5 may be disposed atthe geometric center of the smallest rectangle containing four lightemitting elements 120), but not limited thereto. Note that the shape ofthe aforementioned smallest region may be triangle, rectangle, polygon,circle, ellipse or other suitable shape. The material of the firstspacer SP1 may include any suitable material, such as photoresist, resinor ink, but not limited thereto. Moreover, as shown in FIG. 6, since thedisposition of the first spacer SP1 makes a gap exist between the lightshielding elements 134 and the second control electrode E2, the lightcontroller 130 may further include a diffuser connecting part 132 cdisposed in the gap between the light shielding elements 134 and thesecond control electrode E2, so as to be connected to two adjacentswitchable diffusers 132, wherein the material of the diffuserconnecting part 132 c may be the same as the material of the switchablediffusers 132.

Referring to FIG. 8, FIG. 8 is a schematic diagram showing across-sectional view of a light emitting device according to a thirdembodiment of the present disclosure, wherein the first conductive lineand the second conductive line are omitted in FIG. 8 to make FIG. 8clear. As shown in FIG. 8, a difference between this embodiment and thefirst embodiment is that the light emitting device 300 of thisembodiment further includes the third substrate 310. The lightcontroller 130, the first control electrode E1 and the second controlelectrode E2 may be disposed between the second substrate 140 and thethird substrate 310, wherein the sealant AL is configured to adhere tothe second substrate 140 and the third substrate 310. In themanufacturing method of the light emitting device 300, the formation ofthe structures and components (e.g., the light controller 130, the firstcontrol electrode E1, the second control electrode E2 and the sealantAL, etc.) between the second substrate 140 and the third substrate 310may be completed first, such that the second substrate 140, the thirdsubstrate 310 and the structures and components therebetween form alight controlling board 320. Then, the light controlling board 320 isdisposed on the light emitting elements 120 and the insulating layer150, so as to complete the manufacture of the light emitting device 300.Note that the circuit configured to provide the control signal may bedisposed between the second substrate 140 and the third substrate 310,disposed between the first substrate 110 and the third substrate 310 ordisposed at other suitable position based on requirement(s), and thiscircuit may be electrically connected to the first control electrode E1and the second control electrode E2 through the peripheral traces PT.Furthermore, the third substrate 310 may include glass, quartz,sapphire, polyimide (PI), polyethylene terephthalate (PET), othersuitable material or a combination thereof, so as to be a rigidsubstrate or a flexible substrate.

Moreover, in order to reduce the damage on the light emitting elements120 when the light controlling board 320 is disposed on the lightemitting elements 120 and the insulating layer 150 (e.g., the damage onthe light emitting elements 120 is caused by the pressure which thelight controlling board 320 is disposed on the light emitting elements120), the light emitting device 300 may optionally include a secondspacer SP2 disposed on the first substrate 110, wherein the top of thesecond spacer SP2 may be higher than the light emitting element 120. Theinsulating layer 150 may cover the top of the second spacer SP2, or thetop of the second spacer SP2 is higher than or equal to the top surfaceof the insulating layer 150. For instance, in FIG. 8, the second spacerSP2 may be in contact with the third substrate 310, but not limitedthereto. The second spacer SP2 may include any suitable material, suchas photoresist, resin or ink, but not limited thereto. In addition, dueto the disposition of the second spacer SP2, in the lights emitted bythe light emitting elements 120, the lights having a larger angle withthe normal direction Dn may be blocked, thereby making the lightsemitted by the light emitting elements 120 more concentrated.

Furthermore, each switchable diffuser 132 may be corresponding to (oroverlapped with) one or more of the light emitting elements 120 in thenormal direction Dn. For instance, each switchable diffuser 132 shown inFIG. 8 may be corresponding to (or overlapped with) three light emittingelements 120 in the normal direction Dn, and these three light emittingelements 120 may emit the lights with the same color or differentcolors. In some embodiments, each switchable diffuser 132 may becorresponding to (or overlapped with) three light emitting elements 120respectively emitting red light, green light and blue light in thenormal direction Dn, but not limited thereto.

Referring to FIG. 9, FIG. 9 is a schematic diagram showing across-sectional view of a structure and lights of a light emittingdevice in a first state and a structure and lights of a light emittingdevice in a second state according to a fourth embodiment of the presentdisclosure, wherein the first conductive line and the second conductiveline are omitted in FIG. 9 to make FIG. 9 clear. Note that FIG. 9 usesdifferent shadings to show the switchable diffusers 132 in differentstates, wherein the switchable diffusers 132 in the first state SU1 areshown by sparsely dotted shading, and the switchable diffusers 132 inthe second state SU2 are shown by densely dotted shading. As shown inFIG. 9, a difference between this embodiment and the first embodiment isthe design of the light controller 130 of the light emitting device 400of this embodiment. In this embodiment, the light controller 130 mayinclude two layers, one of the layers is a collimator 410, and the otherlayer is the switchable diffuser(s) 132 disposed on the collimator 410.The collimator 410 may include a plurality of collimating units 410 u,and each collimating unit 410 u may be corresponding to one or more ofthe light emitting elements 120 and configured to make the lightsgenerated by the corresponding light emitting element(s) 120 becollimated, thereby forming the collimated lights Ld. The material andoperation of switchable diffuser 132 may be similar to the firstembodiment, wherein the switchable diffuser 132 may be controlled basedon the control signals received by the first control electrode E1 andthe second control electrode E2, such that the light controller 130 maybe switchable in the first state SU1 and the second state SU2.

In the first state SU1 of this embodiment, the switchable diffusers 132may not adjust the emitted directions (in the light controller 130) ofthe collimated lights Ld (e.g., the switchable diffuser 132 is almosttransparent). Therefore, when the collimated lights Ld enter theswitchable diffuser 132 in the first state SU1, the collimated lights Ldmay directly pass through the illuminating surface LS (e.g., the lightsL3). On the other hand, in the second state SU2 of this embodiment, theswitchable diffusers 132 may adjust the emitted directions (in the lightcontroller 130) of the collimated lights Ld (e.g., the switchablediffuser 132 may make the lights be diffused), and therefore, theilluminating surface LS may emit uniformly diffused lights (e.g., thelights L4). Accordingly, it can be known that, the light controller 130may adjust the collimated lights Ld to make the collimated lights Ld bediffused by the switchable diffuser 132 in the second state SU2. Notethat, in FIG. 9, the illuminating surface LS may be an outer surface ofthe second control electrode E2 or an outer surface of other layerdisposed on the switchable diffuser 132.

Optionally, in the light controller 130, the collimator 410 and theswitchable diffuser 132 are spaced apart from each other by a distance Din the normal direction Dn, and this distance D may not be greater than0.35 mm, but not limited thereto. Owing to the existence of thisdistance D, the switchable diffuser 132 of the light controller 130makes the collimated lights Ld be diffused more uniformly. In addition,for example, in some embodiments, a space between the collimator 410 andthe switchable diffuser 132 may be filled with any suitable transparentmaterial, wherein the transparent material may include such as acrylicresin, epoxy resin and/or silicon resin, but not limited thereto.

Referring to FIG. 10, FIG. 10 is a schematic diagram showing across-sectional view of a structure and lights of a light emittingdevice in a first state and a structure and lights of a light emittingdevice in a second state according to a fifth embodiment of the presentdisclosure, wherein the first conductive line and the second conductiveline are omitted in FIG. 10 to make FIG. 10 clear. As shown in FIG. 10,a difference between this embodiment and the first embodiment is thedesign of the light controller 130 of the light emitting device 500 ofthis embodiment. The light controller 130 of this embodiment include aplurality of the units 532 and a plurality of walls 534, wherein thedisposed positions of the units 532 may be similar to the switchablediffusers of the first embodiment, the walls 534 may be similar to thelight shielding elements of the above embodiment, and the disposedpositions of the walls 534 may be similar to the disposed positions ofthe light shielding elements of the above embodiment. Accordingly, eachof the units 532 may be corresponding to (or overlapped with) at leastone of the light emitting elements 120 in the normal direction Dn, thewalls 534 may be disposed between two adjacent units 532, and the walls534 may not be corresponding to (or not overlapped with) the lightemitting element 120 in the normal direction Dn. For instance, in FIG.10, one of the units 532 may be corresponding to (or overlapped with)one light emitting element 120 in the normal direction Dn, but notlimited thereto. The disposed positions of the units 532 and the walls534 of the light controller 130 may be designed based on requirement(s).For example, in some embodiments (as shown in FIG. 10), the wall(s) 534may surround one unit 532 in top view, and/or two adjacent units 532 maybe completely separated by the wall(s) 534, but not limited thereto.Furthermore, an angle θ between a side wall 534 a of the wall 534 andthe illuminating surface LS may be greater than or equal to 80°, forexample, but not limited thereto. The side wall 534 a may substantiallyextend along an extending direction and may not be a flatten surface,and the angle θ may be between this extending direction and theilluminating surface LS.

In this embodiment, the units 532 of the light controller 130 may betransparent (or almost transparent), such that the lights generated bythe light emitting elements 120 may pass through these units 532. Thewalls 534 may be controlled based on the control signals received by thefirst control electrode E1 and the second control electrode E2, suchthat the light controller 130 may be switchable in the first state SU1and the second state SU2, wherein the light controller 130 may collimatethe lights generated by the light emitting elements 120 in the firststate SU1 and may diffuse the lights generated by the light emittingelements 120 in the second state SU2. Specifically, when the lightcontroller 130 is in the first state SU1, the walls 534 may be in anon-transmissive state; when the light controller 130 is in the secondstate SU2, the walls 534 may be in a transmissive state. Namely, thewalls 534 may be switchable in states of the transmissive state and thenon-transmissive state. In order to make the walls 534 be switchable inthe transmissive state and the non-transmissive state, the first controlelectrode E1 and the second control electrode E2 may be disposedadjacent to the walls 534 of the light controller 130 at least, and thelight emitting device 500 may be switchable in the first state SU1 andthe second state SU2 by providing different control signals for thefirst control electrode E1 and the second control electrode E2. Notethat FIG. 10 uses different shadings to show the walls 534 in differentstates, wherein the walls 534 in the non-transmissive state (the lightcontroller 130 is in the first state SU1) are shown by the shading withgrids, and the walls 534 in the transmissive state (the light controller130 is in the second state SU2) are shown by the shading withnon-continuous tilt lines.

In detail, in the first state SU1 of this embodiment (as shown in FIG.10), the walls 534 are in the non-transmissive state. Hence, before thelights generated by the light emitting elements 120 enter the lightcontroller 130, a portion of the lights (i.e., the lights L1 of whichthe angle with the normal direction Dn is greater) may be blocked by thebottom surface of the walls 534, and another portion of the lights mayenter the units 532 which are transparent, thereby filtering the lights.Then, since the units 532 may not adjust the emitted directions of thelights generated by the light emitting elements 120, and the walls 534are in the non-transmissive state, when the lights generated by thelight emitting elements 120 enter the unit 532, the lights (e.g., thelights L2) of which the angle with the normal direction Dn is greatermay be blocked by the side walls 534 a of the walls 534 in thenon-transmissive state, such that the lights may be collimated and passthrough the illuminating surface LS (e.g., the lights L3). On the otherhand, in the second state SU2 of this embodiment (as shown in FIG. 10),the walls 534 are in the transmissive state (e.g., the walls 534 aretransparent or almost transparent). Hence, the emitted directions of thelights generated by the light emitting elements 120 (the emitteddirections of the lights are various and direct to the illuminatingsurface LS) may not be adjusted and/or filtered by the light controller130 substantially. As the result, the lights may be diffused and passthrough the illuminating surface LS (e.g., the lights L4). Accordingly,it can be known that, in the first state SU1 of this embodiment, thelight controller 130 may collimate the lights by the walls 534; in thesecond state SU2 of this embodiment, the light controller 130 may notadjust and/or filter the lights generated by the light emitting elements120 substantially, so as to make the lights diffused.

Accordingly, the wall 534 and the units 532 may individually include anysuitable material which can achieve the above function. In someembodiments, the refractive index of the unit 532 may range such as from1.4 to 1.9, but not limited thereto. In some embodiments, the unit 532may include acrylic resin, polycarbonate resin, silicon resin, epoxyresin, other suitable transparent material or a combination thereof, butnot limited thereto. In some embodiments, the wall 534 may be made of anelectrochromic material or suspend particles, but not limited thereto.

In addition, in this embodiment, the forming methods of the lightcontroller 130, the first control electrode E1 and the second controlelectrode E2 are not particularly limited. In some embodiments, thefirst control electrode E1 and the second control electrode E2 may berespectively formed on the insulating layer 150 and the second substrate140 by a coating process, a deposition process and/or othersemiconductor process(es), and the walls 534 and the units 532 may beformed on the first control electrode E1 or the second control electrodeE2. Then, the first substrate 110 and the second substrate 140 may beadhered to each other by such as the sealant AL, thereby assembling thefirst substrate 110 and the second substrate 140 to complete themanufacture, but not limited thereto.

Referring to FIG. 11, FIG. 11 is a schematic diagram showing across-sectional view of a structure and lights of a light emittingdevice in a first state and a structure and lights of a light emittingdevice in a second state according to a sixth embodiment of the presentdisclosure, wherein the first conductive line and the second conductiveline are omitted in FIG. 11 to make FIG. 11 clear. Note that FIG. 11uses different shadings to show the walls 534 in different states,wherein the walls 534 in the first state SU1 are shown by the shadingwith grids, and the walls 534 in the second state SU2 are shown by theshading with non-continuous tilt lines. As shown in FIG. 11, adifference between this embodiment and the fifth embodiment is that thelight emitting device 600 of this embodiment further includes a thirdsubstrate 310. The light controller 130, the first control electrode E1and the second control electrode E2 are disposed between the secondsubstrate 140 and the third substrate 310, wherein the sealant AL isconfigured to adhere to the second substrate 140 and the third substrate310, such that the second substrate 140, the third substrate 310 and thestructures and components therebetween form a light controlling board320. The details of the third substrate 310 and the light controllingboard 320 may be referred to the third embodiment of the presentdisclosure, and these will not be redundantly described. Similarly, inorder to reduce the damage on the light emitting elements 120 when thelight controlling board 320 is disposed on the light emitting elements120 and the insulating layer 150 (e.g., the damage on the light emittingelements 120 is caused by the pressure which the light controlling board320 is disposed on the light emitting elements 120), the light emittingdevice 600 may optionally include a second spacer SP2 disposed on thefirst substrate 110, wherein the top of the second spacer SP2 is higherthan the light emitting elements 120. The details of the second spacerSP2 may be referred to the third embodiment of the present disclosure,and these will not be redundantly described. Furthermore, due to thedisposition of the second spacer SP2, in the lights emitted by the lightemitting elements 120, the lights (e.g., the lights L5) having a largerangle with the normal direction Dn may be blocked, thereby making thelights emitted by the light emitting elements 120 more concentrated.

Moreover, in FIG. 11, since a gap exists between the walls 534 and thesecond control electrode E2, the light controller 130 may furtherinclude an unit connecting part 532 c disposed in the gap between thewalls 534 and the second control electrode E2, so as to be connected totwo adjacent units 532, wherein the material of the unit connecting part532 c may be the same as the material of the units 532. Furthermore,similar to the second embodiment of the present disclosure, the lightemitting device may further include a first spacer disposed between thewall 534 and the second control electrode E2, so as to generate theabove gap. The details of the first spacer may be referred to the secondembodiment of the present disclosure, and these will not be redundantlydescribed.

In summary, the light emitting device of the present disclosure maycontrol or adjust the light direction emitted from the illuminatingsurface by the light controller, thereby enhancing the privacy ofviewing and/or preventing specific persons from viewing. Furthermore,compared with the traditional electronic device with the function ofcontrolling the light direction, the light emitting device of thepresent disclosure may be thinner, and/or the light emitting device ofthe present disclosure may have the simplified structure.

Although the embodiments and their advantages of the present disclosurehave been described as above, it should be understood that any personhaving ordinary skill in the art can make changes, substitutions, andmodifications without departing from the spirit and scope of the presentdisclosure. In addition, the protecting scope of the present disclosureis not limited to the processes, machines, manufactures, materialcompositions, devices, methods and steps in the specific embodimentsdescribed in the description. Any person having ordinary skill in theart can understand the current or future developed processes, machines,manufactures, material compositions, devices, methods and steps from thecontent of the present disclosure, and then, they can be used accordingto the present disclosure as long as the same functions can beimplemented or the same results can be achieved in the embodimentsdescribed herein. Thus, the protecting scope of the present disclosureincludes the above processes, machines, manufactures, materialcompositions, devices, methods and steps. Moreover, each claimconstitutes an individual embodiment, and the protecting scope of thepresent disclosure also includes the combination of each claim and eachembodiment. The protecting scope of the present disclosure shall bedetermined by the appended claims.

Those skilled in the art will readily observe that numerousmodifications and alterations of the device and method may be made whileretaining the teachings of the disclosure. Accordingly, the abovedisclosure should be construed as limited only by the metes and boundsof the appended claims.

What is claimed is:
 1. A light emitting device, comprising: a pluralityof light emitting elements for emitting lights; and a light controllerdisposed on the light emitting elements for the lights passing through,which is switchable in a first state and a second state; wherein thelight controller collimates the lights in the first state and diffusesthe lights in the second state.
 2. The light emitting device accordingto claim 1, wherein the light controller is in a single layer structurewhich comprises a plurality of switchable diffusers disposedcorresponding to the light emitting elements and a plurality of lightshielding elements surrounding the switchable diffusers.
 3. The lightemitting device according to claim 2, wherein each of the switchablediffusers is a polymer dispersed liquid crystal cell or a polymernetwork liquid crystal cell.
 4. The light emitting device according toclaim 1, wherein the light controller comprises two layers, one of thelayers is a collimator and the other layer is a switchable diffuserdisposed on the collimator.
 5. The light emitting device according toclaim 4, wherein the two layers are spaced apart from each other by adistance not greater than 0.35 mm.
 6. The light emitting deviceaccording to claim 4, wherein the switchable diffuser is a polymerdispersed liquid crystal cell or a polymer network liquid crystal cell.7. A light emitting device, comprising: a plurality of light emittingelements for emitting lights; and a light controller disposed on thelight emitting elements, comprising a plurality of cells for the lightsfrom the light emitting elements passing through and a plurality ofwalls surrounding the cells; wherein the walls are switchable in statesof a transmissive state and a non-transmissive state.
 8. The lightemitting device according to claim 7, wherein the walls are made of anelectrochromic material or suspend particles.